Prime Minister Victor Ponta, who took office in May, emphasized that the permit only involved exploration activities

"Exploration, yes. After confirmation of the existence or non-existence of shale gas, which would take appreciatively five years, we will take the decision which presumes yes, we will exploit shale gas, while respecting all European and world standards for environmental protection," Ponta said, as cited by Euractiv.

In order to start drilling for shale gas in Eastern Romania, Chevron must also obtain a construction permit.

The EU has so far abstained from commenting on decisions of Member States to ban or allow shale gas drilling.

A recent study published by the EC indicated that there was no need for specific EU legislation on shale gas.

The European Parliament has recommended that Member States adopt national laws to regulate shale gas exploration.

The issue of shale gas drilling has stirred heated debates on a global scale and the method of hydraulic fracturing has been banned in countries like Bulgaria and France over environmental concerns.